 /*******************************************************************************
  * Copyright (c) 2004, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM - Initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.resources.refresh;

 import org.eclipse.core.internal.refresh.InternalRefreshProvider;
 import org.eclipse.core.resources.IResource;

 /**
  * The abstract base class for all auto-refresh providers. This class provides
  * the infrastructure for defining an auto-refresh provider and fulfills the
  * contract specified by the <code>org.eclipse.core.resources.refreshProviders</code>
  * standard extension point.
  * <p>
  * All auto-refresh providers must subclass this class. A
  * <code>RefreshProvider</code> is responsible for creating
  * <code>IRefreshMonitor</code> objects. The provider must decide if
  * it is capable of monitoring the file, or folder and subtree under the path that is provided.
  *
  * @since 3.0
  */
 public abstract class RefreshProvider extends InternalRefreshProvider {
     /**
      * Creates a new refresh monitor that performs naive polling of the resource
      * in the file system to detect changes. The returned monitor will immediately begin
      * monitoring the specified resource root and report changes back to the workspace.
      * <p>
      * This default monitor can be returned by subclasses when
      * <code>installMonitor</code> is called.
      * <p>
      * If the returned monitor is not immediately returned from the <code>installMonitor</code>
      * method, then clients are responsible for telling the returned monitor to
      * stop polling when it is no longer needed. The returned monitor can be told to
      * stop working by invoking <code>IRefreshMonitor.unmonitor(IResource)</code>.
      *
      * @param resource The resource to begin monitoring
      * @return A refresh monitor instance
      * @see #installMonitor(IResource, IRefreshResult)
      */
     protected IRefreshMonitor createPollingMonitor(IResource resource) {
         return super.createPollingMonitor(resource);
     }

     /**
      * Returns an <code>IRefreshMonitor</code> that will monitor a resource. If
      * the resource is an <code>IContainer</code> the monitor will also
      * monitor the subtree under the container. Returns <code>null</code> if
      * this provider cannot create a monitor for the given resource. The
      * provider may return the same monitor instance that has been provided for
      * other resources.
      * <p>
      * The monitor should send results and failures to the provided refresh
      * result.
      *
      * @param resource the resource to monitor
      * @param result the result callback for notifying of failure or of resources that need
      * refreshing
      * @return a monitor on the resource, or <code>null</code>
      * if the resource cannot be monitored
      * @see #createPollingMonitor(IResource)
      */
     public abstract IRefreshMonitor installMonitor(IResource resource, IRefreshResult result);
     
     /**
      * Resets the installed monitors for the given resource. This will remove all
      * existing monitors that are installed on the resource, and then ask all
      * refresh providers to begin monitoring the resource again.
      * <p>
      * This method is intended to be used by refresh providers that need to change
      * the refresh monitor that they previously used to monitor a resource.
      *
      * @param resource The resource to reset the monitors for
      */
     public void resetMonitors(IResource resource) {
         super.resetMonitors(resource);
     }
 }

